clinical definition of blood for 13, 21, 18, x, y fish testing â€“post natal
FISH stands for Fluorescent in Situ Hybridization, and it is a molecular cytogenetic technique which uses fluorescent probes that bind those chromosomes that have a high degree of sequence complementarity. The test is used to detect the presence or absence of specific DNA sequences.
The test is done to find any abnormalities in the chromosomes X and Y and to find the presence of extra autosomal chromosomes 13, 21, 18. The trisomy (3 copies instead of 2) of the chromosome 21 is usually found in children with Down syndrome and that of 18 and 13 is found in Edwards syndrome and Patau syndrome, respectively. These are the most common autosomal chromosomes that are found in live births, as most of the other cases of abnormal chromosomes may lead to miscarriages.
when do you expect results?
Around 1 week Hours
why get tested?
The doctor may ask you to get tested if you want to get your new born screened for any of the following syndromes:
reason to take blood for 13, 21, 18, x, y fish testing â€“post natal test
The test may be ordered by your doctor if -
Your previous pregnancy had some chromosomal abnormality
There have been recurrent miscarriages
You have a family history of chromosomal abnormality
The test will find out if your new born has abnormalities in chromosomes 13, 21, 18, X, or Y.
preparations needed for blood for 13, 21, 18, x, y fish testing â€“post natal test
Your doctor will let you know if there is any need to take any precautions before the test.
Specimen type: Serum (Blood Sample) How is the specimen collected: Through venepuncture collection of blood from a vein within the arm